I couldn't get beamer from the random repository when compiling from TeXworks with MikTeX portable. Beamer works in TeXword but I dislike the interphase, I never use it, I always worked in TeXnic Center with MiKtex, but I cannot install it at the moment, so i've been using the portable MiKtex.
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TrevisSep 21 '10 at 15:09

I've sometimes found that to get things to go landscape, I need to include \usepackage[landscape]{geometry}. That will alter margins, etc, too, but you can set them back to what you want in the options to geometry. Use the layout package to easily find most relevant lengths.
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vandenSep 21 '10 at 17:46